The present invention relates to an apparatus for damage detection for the rope sheath of a synthetic fiber rope.
A synthetic fiber rope is a textile product made from rope threads of natural or chemical fibers, the rope being manufactured by twisting or otherwise forming, by laying in two or more stages with or without sheathing, or by braiding. The rope sheath protectively surrounds the rope structure of so-called synthetic fiber strands and, in the case of driven ropes, creates the necessary tractive capacity. It consists preferably of abrasion-resistant synthetic material, and is connected to the outermost layer of strands by adhesion and/or direct mechanical means. Either the rope sheath surrounds the rope in its entirety, or the outermost rope strands are each surrounded by a sheath of synthetic material and these together form the rope sheath. Especially when the ropes run over pulleys, and/or are driven, the rope sheath is subject to high abrasive wear.
The European patent 0 731 209 shows that a sheathed synthetic fiber rope is known as a suspension element for elevators. To ascertain the state of wear of the rope sheath on this driving rope, the rope sheath has different colors arranged coaxially. At an appropriate amount of wear of the sheath, the underlying color becomes visible, which is then taken to indicate the presence of advanced wear of the rope. This indication of damage has proved its value in relation to effects of wear in the rope sheath, but it is of only limited suitability for the reliable detection of localized damage due, for example, to unintentional contact with sharp edges or the like.